E911 CsLisSubnet and subnet mask

Question

When adding a CsLisSubnet how do you specify the subnet mask?  It appears only an IP is given, how does it know how much of the network provided to use?  For example in the case of 10.0.1.0/23 would I add both 10.0.1.0 and 10.0.2.0?  What
about something smaller than a /24?

Answer 1

You don't specify the subnet mask, it's just a subnet match.  This is straightforward when you have 8/16/24 bit subnets, but isn't obvious when you've got larger or smaller ranges.
Basically, the client will do a calculation, in this case let's say you have 10.0.2.97 as your client's IP.  It will determine based upon the subnet mask given by DHCP or manually assigned that it's on the 10.0.1.0 subnet.  It will then talk
to LIS to see if there's a match against 10.0.1.0  That's it.
I personally wish we could use subnets, for example, let's say you share a subnet over multiple E911 locations, and you want to just take that one 10.0.2.97 IP and give it a different location (perhaps this phone is bolted to the wall), you can't just
stick 10.0.2.97 into your LIS database and have it match, the calculation on the phone or client will come up with 10.0.1.0 and match that, the 10.0.2.97 entry in your LIS database will be ignored because nothing will ever match it.
I hope that's clear.  If not I can explain it differently.
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